diff --git a/lcl/interfaces/win32/win32callback.inc b/lcl/interfaces/win32/win32callback.inc
index f34df25107..05c6c5fc2c 100644
--- a/lcl/interfaces/win32/win32callback.inc
+++ b/lcl/interfaces/win32/win32callback.inc
@@ -293,7 +293,9 @@ end;
 type
   TAccessCustomEdit = class(TCustomEdit);
 
-  TWindowProcHelper = object
+  { TWindowProcHelper }
+
+  TWindowProcHelper = record
   private
     // WindowProc parameters
     Window: HWnd;            // DWord / QWord
@@ -2667,7 +2669,7 @@ function
 var
   Helper: TWindowProcHelper;
 begin
-  helper := default(TWindowProcHelper);
+  FillChar(Helper, SizeOf(TWindowProcHelper), 0);
   Helper.Window := Window;
   Helper.Msg := Msg;
   Helper.WParam := WParam;
diff --git a/lcl/interfaces/win32/win32int.pp b/lcl/interfaces/win32/win32int.pp
index 616245853d..645933fe51 100644
--- a/lcl/interfaces/win32/win32int.pp
+++ b/lcl/interfaces/win32/win32int.pp
@@ -19,6 +19,7 @@
 unit Win32Int;
 
 {$mode objfpc}{$H+}{$T-}{$message warning Fix implicit pointer conversions}
+{$ModeSwitch advancedrecords}
 {$I win32defines.inc}
 
 interface